Applying Boolean Operations
The Boolean operations of union, intersect, and subtract are available for multiple regions of interest and multi-ROIs. You can choose to create new regions of interest of multi-ROIs that are the result of Boolean operations, or to update existing regions of interest.
Boolean operations
The following options are available for all Boolean operations.
| Description | |
|---|---|
|
Destination |
You can choose to create a new object or to modify an existing object as the result of a Boolean operation with the options in the Destination drop-down list.
|
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Keep empty labels |
If selected, all original labels will be retained, even if there are no associated labeled voxels. |
Uniting and Intersecting Regions of Interest
Refer to the following instructions for information about uniting and intersecting regions of interest.
| Description | |
|---|---|
|
Union |
Unites the selected regions of interest. All labeled voxels in the selected ROIs will be included in the designated destination. |
|
Intersect |
Intersects common areas of selected regions of interest. Only labeled voxels common to all selected ROIs will be included in the designated destination. |
How to Unite and Intersect Regions of Interest
- Select the regions of interest you plan to unite or intersect.
To select multiple regions of interest, Ctrl-click the required regions of interest in the Data Properties and Settings panel.
The Boolean operations box appears in the Data Properties and Settings panel.
- Choose a destination for the result of the operation — either a new region of interest or an existing ROI — in the Destination drop-down menu.
- Check the Keep empty labels option if you want to retain all of the original labels.
- Click the Union or Intersect button.
- Do the following if you chose a new region of interest as the destination:
- Select either ROI or Multi-ROI in the New Region of Interest dialog.
- Change the default name and/or color for the new ROI or multi-ROI, as required.
- Choose a geometry for the new file in the Geometry drop-down menu, as required.
- Click the OK the apply the selected Boolean operation.
Subtracting Regions of Interest
Refer to the following instructions for information about subtracting a region of interest from another. You should note that this operation can only happen between two regions of interest.
| Description | |
|---|---|
|
A - B |
Subtracts a region of interest from another. The resulting new region of interest is the difference between the two ROIs. |
|
B - A |
Subtracts a region of interest from another. The resulting new region of interest is the difference between the two ROIs. |
How to Subtract Regions of Interest
- Select the required regions of interest.
The designations A and B are assigned based on the order that the regions of interest were selected.
The Boolean operations box appears in the Data Properties and Settings panel.
- Choose a destination for the result of the operation — either a new region of interest or an existing ROI — in the Destination drop-down menu.
- Check the Keep empty labels option if you want to retain all of the original labels.
- Click the A - B or B - A button, as required.
- Do the following if you chose a new region of interest as the destination:
- Select either ROI or Multi-ROI in the New Region of Interest dialog.
- Change the default name and/or color for the new ROI or multi-ROI, as required.
- Choose a geometry for the new file in the Geometry drop-down menu, as required.
- Click the OK the apply the selected Boolean operation.
Removing or Keeping Intersecting Labels
Refer to the following instructions for information about removing or keeping intersected labels.
| Description | |
|---|---|
|
Remove Intersected |
Automatically removes all labeled components of the initially selected item that intersect with the labels of other regions of interest or multi-ROIs selected for the operation. |
|
Keep Intersected |
Automatically keeps only the labeled components of the initially selected item that do not intersect with the labels of other regions of interest or multi-ROIs selected for the operation. |
How to Keep to Remove Intersecting Labels
- Select the required regions of interest.
To select multiple regions of interest, Ctrl-click the required regions of interest in the Data Properties and Settings panel.
The Boolean operations box appears in the Data Properties and Settings panel.
- Choose a destination for the result of the operation — a new region of interest or an existing ROI — in the Destination drop-down menu.
- Check the Keep empty labels option if you want to retain all of the original labels.
- Click the Remove Intersected or Keep Intersected button, as required.
- Do the following if you chose a new region of interest as the destination:
- Select either ROI or Multi-ROI in the New Region of Interest dialog.
- Change the default name and/or color for the new ROI or multi-ROI, as required.
- Choose a geometry for the new file in the Geometry drop-down menu, as required.
- Click the OK the apply the selected Boolean operation.
